fix: complete the docs/→design/ and openapi→api/ rename references

The file moves (docs/ → design/, docs/api/openapi.json → api/openapi.json) landed
in d01a8fd, but the matching reference updates did not — so mgmt.rs's drift-test
`include_str!("../../../docs/api/openapi.json")` pointed at a path that no longer
exists and the host failed to build. This restores it and updates every reference:

  - mgmt.rs include_str! → ../../../api/openapi.json (fixes the build)
  - web/orval.config.ts codegen target, web/Dockerfile, .dockerignore
  - deb/rpm/Arch packaging install paths
  - CLAUDE.md, the .gitea CI workflows, code doc-comments, design-doc cross-links

docs-site route URLs (/docs/...) untouched.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/punktfunk-host/src/gamestream/crypto.rs

@@ -1,7 +1,7 @@
 //! Pairing crypto primitives (control plane only — distinct from `punktfunk_core`'s AES-GCM
 //! data-plane sealing). GameStream pairing uses: AES-128-**ECB** with **no padding**,
 //! SHA-256 (host appversion major ≥ 7), and RSA-PKCS1v15-SHA256 signatures. See the
-//! `serverinfo + pairing` section of `docs/research/gamestream-protocol-research.json`.
+//! `serverinfo + pairing` section of `design/research/gamestream-protocol-research.json`.
 
 use aes::cipher::generic_array::GenericArray;
 use aes::cipher::{BlockDecrypt, BlockEncrypt, KeyInit};